The batch consisting of 2 steam generators for the 4nd power unit of Akkuyu NPP was delivered to the Eastern Cargo Terminal. After successfully unloading the cargo ship with the aid of a heavy crawler crane, the steam generators were transferred by a special commission to the temporary storage area where access control, equipment quality and integrity inspection will be carried out.
The steam generators were shipped by road from the factory of the manufacturing company Atommash A.Ş. (Volgodonsk, Russia) to the port on the shore of the Tsimlyansk reservoir and loaded on a cargo ship there. Departing from Volgodonsk, the ship sailed to the Sea of Azov over the Don River, passed through the Black Sea, the Sea of Marmara, the Aegean Sea and the Mediterranean, finally reaching its destination, the Eastern Cargo Terminal at the Akkuyu NPP construction site. The length of the sea route was about 3000 km, while the total weight of the cargo exceeded 1800 tons.
AKKUYU NUCLEAR INC. First Deputy General Manager – NGS Construction Director Sergei Butckikh commented on this logistics operation: “The transportation of large-sized equipment for Akkuyu NPP is generally carried out using land and sea routes. The carrier takes into account many details, carefully considers the route to transport the cargo and controls every stage of loading. For example, additional deepening work was carried out for the transportation of this batch of steam generators and for the ship to move smoothly at the quay at the Tsimlyansk reservoir. Meanwhile, preparations for the installation of steam generators in the reactor compartment of Power Unit 1 are nearing completion. Once they are installed, we will begin welding the key circulation pipeline connecting the main equipment of the first cycle.”
Steam generators are among the main equipment of the first cycle of NPP. The first cycle consists of a nuclear reactor, main circulation pumps, main circulation pipeline, pressure stabilizer and safety systems complex. The steam generator is a 355-tonne heat exchanger in which horizontally placed pipes are completely immersed in a chemically desalinated water refrigerant. The refrigerant in the first cycle circulates inside the heat exchanger pipes. In the upper part of the body, there is the space where the steam is produced, and in the lower part, there is the heat exchanger surface consisting of 11.000 pipes. When all the tubes of a steam generator are straightened and spliced together, their total length exceeds 140 km. The steam formed in the steam generators is sent to the turbine through the steam pipelines of the second cycle, where the steam pressure rotates the shaft of the steam turbine. The rotation of the shaft is transferred to the electric generator, where the mechanical energy is converted into electricity.
Steam generators are equipment with a long production cycle, and the total duration of all production processes from the beginning of the production of metallurgical semi-finished products to shipment takes about two years. The production cycle includes welding the individual elements to form the body, fabrication of the bases, drilling of the first-cycle collectors, manufacture and installation of the heat exchanger pipes, interior protection parts, as well as a series of control activities. Before the steam generators are sent from the factory of the manufacturer, they must undergo hydraulic and vacuum tests, all technological openings are closed with special plugs and pressurized nitrogen is injected into the body. Thus, the reliability and robustness of the equipment to be used in NPP are confirmed.